1. Field of the Invention
The present invention relates to a method and apparatus of scheduling a bandwidth in a cable network, and more particularly to bandwidth allocation of an upstream channel in a cable network based on a Data-Over-Cable Service Interface Specifications (DOCSIS) 3.0 standards.
2. Description of Related Art
Since a Data Over Cable Service Interface Specifications (DOCSIS), that is, a data transmission protocol in a DOCSIS 3.0 standards hybrid fiber coax (HFC) network may have a structure controlling each modem based on a time slot, in which a Time Division Multiplexing (TDM) scheme is used in a downstream and a Time Division Multiple Access (TDMA) scheme is used in an upstream, Quality of Service (QoS) may be applicable to multimedia data being sensitive to a Voice over Internet Protocol (VoIP) or delay in a DOCSIS layer.
Multicast in the DOCSIS 3.0 may newly add a DOCSIS specific control protocol between a Cable Modem Termination System (CMTS) and a Cable Modem (CM).
Also, in the DOCSIS standards, an Allocation MAP (MAP) scheduling algorithm implemented in the CMTS may be selectively implemented according to manufacturers without defining specific standards with respect to the MAP scheduling algorithm.
DOCSIS 2.0 may support a maximum downstream service of 42 Mbps and a maximum upstream service of 30 Mbps using a single upstream channel and a single downstream channel, however, DOCSIS 3.0 may concurrently use multiple channels bonded in a modem, thereby increasing a bandwidth.
Accordingly, there arises a need for channel bandwidth allocation which may reduce a bandwidth request collision in the DOCSIS 3.0 network using channel bonding, thereby reducing a network delay time.